Companies that rely on broadcast video and/or audio programs for revenue, such as advertisers, television networks and content providers, wish to know the size and demographic composition of the audience(s) that consume their program(s). Audience measurement companies address this need by measuring the demographic composition of a set of statistically selected households and the program consumption habits of the member(s) of those households. For example, audience measurement companies may collect media consumption data from a selected household by monitoring the content displayed on that household's television(s) and by identifying which household member(s) are watching that content.
Traditionally, broadcast programs have been consumed at the time of broadcast. Therefore, it was safe to assume that audience members using an information presenting device such as a television or radio consumed the entire broadcast stream during the period in which the information presenting device was in use. Recently, however, recording devices such as audio cassette players, video cassette recorders (VCR's), set top boxes (STBs), digital video recorders (DVRs), and personal video recorders (PVRs) such as the TiVo® product and other devices that permit content to be recorded and replayed in accordance with the desires of the audience members have become commonplace. Additionally, the introduction of video on demand (VOD) and internet streaming services allows consumers to request media content to be presented according to their desire. These devices and services have increased the audience members' ability to time-shift the consumption of broadcast programs (i.e., to record a program at the time of broadcast and consume that same program at a later time or to retrieve and present media content at any time). The ability to time-shift media content has also provided the consumer with enhanced power to consume only selected portions of broadcast programs by, for example, skipping or fast-forwarding through portions of recorded content. Some consumers have used this enhanced ability to avoid viewing advertising commercials or other portions of the broadcast program.